Malaria transmission in landscapes with varying deforestation levels and timelines in the Amazon: a longitudinal spatiotemporal study

Abstract

The relationship between deforestation and malaria is a spatiotemporal process of variation in Plasmodium incidence in human-dominated Amazonian rural environments. The present study aimed to assess the underlying mechanisms of malarial exposure risk at a fine scale in 5-km2 sites across the Brazilian Amazon, using field-collected data with a longitudinal spatiotemporally structured approach. Anopheline mosquitoes were sampled from 80 sites to investigate the Plasmodium infection rate in mosquito communities and to estimate the malaria exposure risk in rural landscapes. The remaining amount of forest cover (accumulated deforestation) and the deforestation timeline were estimated in each site to represent the main parameters of both the frontier malaria hypothesis and an alternate scenario, the deforestation-malaria hypothesis, proposed herein. The maximum frequency of pathogenic sites occurred at the intermediate forest cover level (50% of accumulated deforestation) at two temporal deforestation peaks, e.g., 10 and 35 years after the beginning of the organization of a settlement. The incidence density of infected anophelines in sites where the original forest cover decreased by more than 50% in the first 25 years of settlement development was at least twice as high as the incidence density calculated for the other sites studied (adjusted incidence density ratio = 2.25; 95% CI, 1.38–3.68; p = 0.001). The results of this study support the frontier malaria as a unifying hypothesis for explaining malaria emergence and for designing specific control interventions in the Brazilian Amazon.

Causal effects on low Apgar at 5-min and stillbirth in a malaria maternal–fetal health outcome investigation: a large perinatal surveillance study in the Brazilian Amazon

“…falciparum -infected anophelines from rural Cruzeiro do Sul [ 37 – 41 ]. Laporta et al [ 40 ] showed that urban and/or peri-urban malaria is mainly caused by P . vivax -infected anophelines (Fig.…”

“…5 C) and 1.4% (3/210) in rural settlements (Fig. 5 D, E) [ 40 ]. Plasmodium falciparum -infection rate in anophelines is 2.6% (4/153) in the rural settlement Ramal do Caraca (Fig.…”

“…Plasmodium falciparum -infection rate in anophelines is 2.6% (4/153) in the rural settlement Ramal do Caraca (Fig. 5 E) [ 40 ]. This adds further complexity to interpretating the study findings in that: (1) urban/peri-urban sites have higher Plasmodium -infection rate (24% vs. 1.4%) than rural settlements (Fig.…”

“…falciparum -infection rate (2.6%) is only present in rural settlements (Fig. 5 E) [ 40 ]. Having rural living as a strong predictor of maternal–fetal health outcomes can have therefore three straightforward and non-mutually exclusive interpretations: (1) lower access to malaria commodities (diagnosis and treatment) in rural settlements, (2) higher rate of undiagnosed submicroscopic P .…”

The Grass Was Greener - Climate Change, One Health, and the High Hopes to Mitigate COVID-19, Avian Influenza, and other Zoonotic Emerging Diseases

“…On the other hand, the impact of environmental deleterious human activities, such as deforestation can lead to an increase or shift of selection pressures on different pathogens, particularly viruses (Kalbus et al, 2021;Laporta et al, 2021), Figure 1). Such is the case of SARS-CoV-2, whose origin remains largely unknown (Mohammed, 2021; The Lancet Infectious, 2021) although recent findings have revealed that 96.2% of its genome shares similarities with bat- related coronaviruses; thus, suggesting its probable origin from Chiroptera (Zhou et al, 2020;Bonilla-Aldana et al, 2021).…”